In one variation of the experiments, researchers asked kids around age four to sit down at a table with a pair of marshmallows.

The experimenter would then leave the room, telling the tyke that they could eat one marshmallow now or wait for their return, thus scoring two sugary treats.

Watching the footage, you can see the extreme steps kids took to avoid the sweet temptation.

A girl turns away, refusing to look. Another just folds her arms and puts her head down, miming sleep. Another starts talking to herself like Charlie Chaplin, issuing self-instructions not to submit to her impulses.

“That’s executive function that you see right here,” explains the 84-year-old Mischel, who’s now a professor at Columbia University after a long tenure at Stanford.

As Mischel details in his new book, “The Marshmallow Test: Mastering Self-Control,” decades of his and others’ research have shown that executive function is a massive predictor of success, from academic achievement to career growth and even marital stability.

In honour of the new book, we talked to him about what self-control is, why it’s so important to success, and how we can hack our habits to be more in line with our goals.

Business Insider: Why does this seemingly simple act of delaying gratification have all of these massive consequences?

Walter Mischel: Let’s start with an example. If I want to reach the goal I have in mind — I want the two marshmallows — I have to inhibit interfering responses. I can’t start looking at the marshmallows and thinking how yummy and chewy the marshmallow is or how sweet it will taste. I can’t start touching it too much because I’ll want to bring it right up to my mouth.

What I need to do is to use my attention in order to monitor my progress towards the goal, and do whatever I need to do to make it possible.

BI: OK, so why are the kids that resist the marshmallows better off than the others?

WM: Because planning and other future-oriented activities and ways of controlling one’s own emotions require executive function.

These fundamental skills allow you to have control over stimuli rather than being controlled by them.

That’s true whether we’re talking about marshmallows, smoking tobacco, controlling your rage at your employer so that you don’t get fired, controlling your emotions so that you won’t mess up your relationships. You have keep in mind what the consequences are if you don’t regulate your emotions.

BI: How exactly does self-control build a pattern of success?

WM: The cognitive skills that enable self-control are fundamental, but you also need other motivations and to have a reason to activate and use those skills.

One of the ways that the connection between self-control and success begins early is in school. The kids who succeed in the marshmallow test have the advantage of accumulated realistic success experiences. They start to develop the expectation of: “I think I can. I really am somebody who can do it.”

BI: This is a special request from my editor. She wants to know how she can keep jogging every morning, even when the weather gets cold.

WM: I think one of the most effective things to do is to have a specific If/Then implementation plan.

First of all, she needs to understand that what is happening is that the pleasure value of jogging is going down and the effort value and the discomfort value of jogging is going up.

So this is really an instinctive question and she has to ask herself, “How much is this really worth to me?”

BI: And if it’s worth it?

WM: If it is, then she has to heed the delayed consequences. She has to say, “I do want to be in great shape, this is vehemently important to me, so I’m going to have an If/Then plan, which is when it’s 7 a.m. and the alarm rings, I put on my warmest jogging clothes, and I go.”

Then it becomes as automatic as brushing your teeth, which is not at all a natural thing. Our hardwired system doesn’t have us brushing our teeth.

So the advice to your editor is to figure out if she really wants to change her discounting equation. Does she want to increase, for her, the value of the delayed consequences sufficient to offset the increased effort cost that comes from jogging and crappy weather. It’s an actual decision she can make.

If she’s serious about it, then she makes an automatic If/Then plan so it’s like jumping in the shower, even though you don’t feel like it. It’s automatic.